package com.ssm.controller;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.util.MultiValueMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.UUID;

/**
 * Author  zxy
 * Date  2022/11/19 上午 8:44
 */
@Controller
public class FileUpAndDownController {

    /*
    * 文件下载
    * */
    @RequestMapping("/test/down")
    public ResponseEntity<byte[]> testResponseEntity(HttpSession session) throws IOException {
        // 获取ServletContext对象
        ServletContext servletContext = session.getServletContext();
        // 获取服务器中文件的真实路径
        String realPath = servletContext.getRealPath("/img/1.jpg");
        // 创建输入流
        InputStream is = new FileInputStream(realPath);
        // 创建字节数组
        byte[] bytes = new byte[is.available()];
        // 将流读到字节数组中
        is.read(bytes);
        // 创建HttpHeaders对象设置响应头信息
        MultiValueMap<String, String> headers = new HttpHeaders();
        // 设置要下载方式以及下载文件的名字
        headers.add("Content-Disposition", "attachment;filename=1.jpg");
        // 设置响应状态码
        HttpStatus statusCode = HttpStatus.OK;
        // 创建ResponseEntity对象
        ResponseEntity<byte[]> responseEntity = new ResponseEntity<>(bytes, headers, statusCode);
        // 关闭输入流
        is.close();
        return responseEntity;
    }

    /*
    * 文件上传
    * */
    @RequestMapping("/test/up")
    public String testUp(MultipartFile photo, HttpSession httpSession) throws IOException {
        // 获取上传文件名
        String filename = photo.getOriginalFilename();
        // 获取文件后缀
        String subname = filename.substring(filename.lastIndexOf("."));
        // 获取uuid
        String uuid = UUID.randomUUID().toString();
        // 拼接新的文件名
        filename = uuid + subname;
        // 获取servletContext对象
        ServletContext servletContext = httpSession.getServletContext();
        // 获取当前工程的真实路径
        String photoPath = servletContext.getRealPath("photo");
        // 创建所对应的File对象
        File file = new File(photoPath);
        // 判断file是否存在
        if(!file.exists()) {
            file.mkdir();
        }
        String finalPath = photoPath + File.separator + filename;
        // 上传文件夹
        photo.transferTo(new File(finalPath));
        return "success";
    }

}
